Back for doctor blades



May 5, 1964 w. P. DAPSES BACK FOR DOCTOR BLADES Filed Bat. 14, 1962 m SM m D WP L i W ATTORNEY United States Patent 3,131,415 BACK FOR DOCTGRBLADES William P. Dapses, Salem, Greg, assignor to Lodding EngineeringCorporation, Auburn, Mass, a corporation of Massachusetts Filed Dec. 14,1962, Ser. No. 244,634 7 Claims. (Cl. 15-25651) This invention relatesto a new and improved doctor back construction and particularly to asimplified construction, together with means for damping vibrations inthe doctor blade when it is used in its ordinary function of scrapingroll surfaces and the like.

The present construction involves a relatively simple elongated hollowtubular member on or in which is mounted an elongated flat rectangularplate, this plate having an edge extending exteriorly of the elongatedtubular member and having mounted thereon a blade holder and a blade,said tubular member being mounted more or less in the usual manner byjournals at the ends thereof and being filled with a pourable, discretematerial such as sand which acts as a damping agent for the doctor bladewhich would otherwise tend to vibrate.

Further objects of the invention also include the application of heavierweight to the sand or similar material which is used to fill the tubularmember and this can take the form of a discrete metal for instance leadshot or the like which is dispersed throughout the sand and which lendsfurther weight to the construction at a relatively small cost in orderto provide a simple inexpensive doctor back which, however, is providedwith the combination of sand and lead shot to provide against unwantedvibration.

The invention further relates to arrangements and combinations of partswhich will be hereinafter described and more particularly set forth inthe appended claims.

Reference is to be had to the accompanying drawings; in which FIG. 1 isa view in elevation with parts cut away illustrating the invention;

FIG. 2 is a section on line 22 of FIG. 1, and

FIG. 3 is an end View, looking in the direction of arrow 3 in FIG. 1.

Referring to the drawings in detail, the reference numeral 19 indicatesa roll surface being doctored. This roll is mounted in any way desiredand extends across the machine frame in the usual way. On the machineframe at opposite sides thereof there are mounted brackets 12 upon whichare mounted doctor journal bearings 14 swivelly mounting doctor journals16, these being aligned and capable of being oscillated by means of forinstance a hydraulic or pneumatic cylinder 18 in order to apply greateror less pressure of the doctor blade to the surface being doctored as iswell known in the art. The hydraulic or pneumatic cylinder 18 is mountedin any way desired on the machine frame as for instance upon structuralbrackets 29 which may be in turn hung or suspended from brackets 12 andthe cylinder has a pivot connection 22 with an arm 24 mounted at 26 fastto the journal 16 in the usual manner.

The two journals 16 pivotally mount between them an elongated hollowtubular member generally indicated by the reference numeral 28. Thismember is preferably made of aluminum or other light weight material forreducing the overall weight and cost of the usual doctor bladeconstruction. However, the tubular member 28 may be of any crosssectional form. It is here shown as cylindrical and of course it extendsfrom end-to-end of the roll 10.

Diametrically mounted the entire length of tubing 28 there is a plateindicated at 34?, this plate being elongated, fiat and having paralleledges. It extends completely across the tubular member 28 essentiallydividing the lat- 3,131,415 Patented May 5., 1964 ter into two halvesand as a matter of fact the tubular member 28 may be fabricated in thismanner. In any event, the plate 30 extends at 32 outwardly diametricallyf tubular member 28 and carries at its forward edge a conventional bladeholder 34 in turn carrying a conventional blade 36.

The ends of the tubular member 28 are closed by end plates as indicatedat 38 and any conventional means such as bolts or the clips shown at 40can be'used to secure the parts together. The tubular member 28 issubstantially filled with a heavy, pourable, discrete vibration dampingmaterial such as for instance sand. As much or as little sand may becontained within tubular member 28 as is found desirable in order todampen the vibration to the degree necessary. The sand is easily pouredinto the tubular member upon removal of one of the end plates 38. Thesand adds weight to the construction to provide the damping effectdesired.

In the event that additional damping is found to be required, thenheavier material can be dispersed throughout the sand as for instancelead shot. The sand and shot combination forms an extremely easycompound material to handle and to apply to the tubular member 28 and ofcourse the proportions of sand and shot can be varied to suit anyconditions which may be encountered.

It is found that the sand tends to dampen vibrations within a certainrange of relatively short wave length whereas the lead shot tends todampen vibrations of longer wave length. Thus it is seen that in somecases where only relatively short wave length vibrations areencountered, only the sand or similar material is necessary to be used.

0n the other hand where longer wave lengths of vibration areencountered, then the combination of the sand and the lead shot is foundto be very effective in essentially dampening out both the long andshort wave vibrations which may be encountered under differentconditions of operation of the doctor.

This forms an inexpensive doctor supporting construc tion and the sandand the shot also are relatively inexpensive materials by which todispense with unwanted vibrations in different ranges.

Having thus described my invention and the advantages thereof, I do notwish to be limited to the details herein disclosed, otherwise than asset forth in the claims, but what I claim is:

1. A doctor blade supporting construction comprising an elongated hollowmember, a plate extending transversely across said hollow member and atleast partially exteriorly thereof in the same plane along one side edgeof the hollow member, a doctor blade holder on the exterior edge of theplate and a doctor blade on the holder,- means fixedly mounting theholder directly onto the plate, means fixedly mounting the blade on theholder, the blade thereby being in supported, fixed relation to theplate, and means for damping vibrations encountered in the operation ofthe doctor blade in scraping a surface, said means comprising a fiowablediscrete relatively heavy material held in the hollow member.

2. The doctor blade supporting construction recited in claim 1 whereinthe damping material substantially fills the hollow member.

3. The doctor blade supporting construction recited in claim 1 whereinthe damping material consists of sand;

4. The doctor blade supporting construction recited in claim 1 whereinsaid damping material comprises at least two different discretematerials mixed together, said materials having ditferent densitieswhereby vibrations of different wave length are dampened.

5. The doctor blade supporting construction recited in claim 1 whereinsaid damping material comprises at least two different discretematerials of different densities, one being in the nature of leadparticles.

6. The doctor blade supporting construction recited in claim 1 whereinsaid damping material comprises at least two different discretematerials of different densities, one being in the nature of leadparticles and the other material comprising lighter weight particles.

7. The doctor blade supporting construction recited in claim 1 whereinsaid damping material comprises at least two different materials ofdifferent densities, one being in the nature of lead shot and the othermaterial comprising lighter weight particles, said lighter weightparticles being in the nature of sand.

References Cited in the file of this patent UNITED STATES PATENTS2,330,889 Holcomb Oct. 5, 1943 2,808,227 Danel Oct. 1, 1957 FOREIGNPATENTS 532,467 Germany Aug. 28, 1931

1. A DOCTOR BLADE SUPPORTING CONSTRUCTION COMPRISING AN ELONGATED HOLLOWMEMBER, A PLATE EXTENDING TRANSVERSELY ACROSS SAID HOLLOW MEMBER ANS ATLEAST PARTIALLY EXTERIORLY THEREOF IN THE SAME PLANE ALONG ONE SIDE EDGEOF THE HOLLOW MEMBER, A DOCTOR BLADE HOLDER ON THE EXTERIOR EDGE OF THEPLATE AND A DOCTOR BLADE ON THE HOLDER, MEANS FIXEDLY MOUNTING THEHOLDER DIRECTLY ONTO THE PLATE, MEANS FIXEDLY MOUNTING THE BLADE ON THEHOLDER, THE BLADE THEREBY BEING AN SUPPORTED, FIXED RELATION TO THEPLATE, AND MEANS FOR DAMPING VIBRATIONS ENCOUNTERED IN THE OPERATION OFTHE DOCTOR BLADE IN SCRAPING A SURFACE SAID MEANS COMPRISING A FLOWABLEDISCRETE RELATIVELY HEAVY MATERIAL HELD IN THE HOLLOW MEMBER.